Gun barrel cooling means



June 9, 1953 `c. E. BALLElsEN 2,641,162

GUN BARREL COOLING MEANS Charla Bullei .5B1-L June 9, 1953 c. E.BALLElsEN 2,541,162

GUN BARREL COOLING MEANS Filed Feb. 4, 1942 3 Sheets-Sheet 2 June 9,1953 c. E. BALLElsEN 2,641,152

GUN BARREL COOLING MEANS Filed Feb. 4, 1942 5 Sheets-Sheet 3 iEiglmgmc/who@ Chur'le s E- Bull Ei .sen

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Patented June 9, 1953 GUN BARREL COOLING MEANS Charles E. Balleisen,Philadelphia, Pa., assignor to the United States of America asrepresented by the Secretary of War Application February 4, 1942, SerialNo. 429,496 1o claims.Y (C1. sia-14.1)

(Granted under Title 35, U. s. code 1952),

" sec. 266) The invention described herein may be manufactured and usedby or for the Government for governmental purposes, without the paymentto me of any royalty thereon.

`|This invention relates to means for introducing `fluid into theinterior portions of the barrel of a firearm.,

An object oi this invention is to provide means for jecting uid into thebarrel ot an automatic firearm immediately after each round ofammnitionis ered.

' Another object of this invention is to provide a compact valve,especially adapted to be used with a firearm for introducing apredetermined amount of uid into the barrel of an automatic firearmimmediately after each round of ammunition is iired.

Another `object of this invention is to provide means for injectingcooling fluidinto the barrel ofr an automatic r'earm in such a quantitythat thecooling fiuid which may be water, flashes into the gaseousstate'and maintains the barrel at a safe operating temperature.

ThisH invention has speciiic application to a barrel of .50 caliber butit is understood that this invention may be applied to barrels ofgreater and smaller caliber. Suiiicient fluid, preferably water, isyintroduced in the gun barrel so as to maintain the final steady statetemperature of the gun barrel under continuous operation atapproximately 300 F. when the gun is operated continuously; however,this temperature may be subject to variation and the onlyapparent'limitation on that temperature appears to, be based on thefollowing considerations; that at the higher range the temperatureshould not be destructive to the barrel material and at the lower rangethe temperature should be high enoughA to vaporize the cooling iiuidwhich is introduced.

In the cooling of automatic guns by the particular means disclosedherein it is fundamental to realize' that the valve for introducing thefluid into 'the gun barrel should be cap-able of being placed in thosepositions where the introduction of uid will produce the greatestcooling effect. Since the time available for injection of the fluid intothe barrel between rounds is approximately .02 second and since a fewcubic centimeters of water must be introduced into the barrel of a .50cal. gun in that short period of time, it follows that a quickresponsive valve is necessary and that it should be so positionedl onthe gun barrel that one or more conduits through the barrel Wall willnot seriously alter the mechanical strength of the barrel.

In general, there are four methods of operating an inlet valve for theinjection of a cooling liquid into a barrel of an automatic-gun duringthe period of ammunition extracting and loading. These four methods maybe classined as follows:

1. Recoil 2. High pressure 3. Low pressure (muzzle) gas` 4. Bullet ormuzzle blast The fourth method is generally dismissed as being inferiorto the others. Means are disclosed herein for carrying out any one ofthe iirst three methods. n

The rst three methods outlined above are beset with advantages anddisadvantages. In general, the recoil method hasl the followingadvantages: (1) mechanical motion is directly available, (A2) mechanismis simple, and (3,) there is an irmerent controlled time delay; thedisadvantages are as follows: (l) the operating reserve ofthe gun isreduced, and (2) there is a danger of flooding the barrel before ring,

In general, the second method incorporating high pressure gas has thefollowing advantages: (1) the mechanism is simple, and (2) there is noappreciable energy extracted from the gun; the disadvantages are asfollows: (1) mechanical motion must be produced, (2) a time delay mustbe provided, and"(3) an adequate seal preventing the loss of gas mustbe` provided.

In general, the third method incorporating low pressure gas has thefollowing advantages: (l) no appreciable energy is extracted from thegun, and (2A)` an inherent time delay is introduced; the disadvantage isas follows: (l) the mechanisrn is complicated. n

'Irhe specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in 'the accompanying drawings in which:

Fig. 1 is a side view of a portion of a Browning automatic machine gunwith a fluid valve and its actuating mechanism mounted thereon. Thebreech bolt E of the gun is in its furthermost rear position andcorrespondingly the iiuid valve allows passage of fluid;

Fig, '21 is a plan view of the assembly shown in Fig. 1;

Fig. 3 isv an end View of the fluid valve and its actuating mechanismtaken substantially on line 3--3 oflFi-g. 2;v the pertinent portionsofthe rearm are shown dotted;

Fig. 4 is a sectional View taken substantially on, une 4f-i of; 3 z

Fig. 5 is a side view of a portion of a gun barrel with a fluid valvehoused therein; the valve is adapted to be actuated by pressuredeveloped in the barrel bore synchronously with the rate of fire' of,for example, a Browning machine gun;

Fig. 6 is a section through the iiuid valve and barrel takensubstantially on line 6-6 of Fig. 5; the valve is shown in its normalposition or furthermost down position;

Fig. '7 is a section similar'to the section of Fig. 6 but in thisinstance the cup shaped valve member I3 has been displaced from itsnormal position up to its highest position vduetojammunition gaspressure on the bottom of cup shaped member |3;

Fig. 8 is a section similar yto 't theV section:- of Fig. 6 but in thisinstance the cup shaped valve member I3 has receded from its highestposition of Fig. '7 to the position shown wherein cooling fluid may flowfrom channel I8 or I9 into the barrel bore;

Fig. 9 is a section taken substantially through the bottom of the cupshaped member on line 0 9 of Fig. 8;

Fig. 1) is a longitudinal section taken substantially through the centerof the barrel and through the center of valve actuating mechanism whichis responsive to ammunition gas pressure at the muzzle of the iirearm.The mechanism in this instance is shown in its most forward position;

Fig. 11 is a section similar to the section of Fig. but in this instancethe valve mechanism is lin its extreme rear position corresponding toValve opening position;

Fig. 12 is a section taken substantially on line |2|2of Fig. 10;

Fig. 13 is an end view taken substantially on the direction of line|3-I3 of Fig. 11.

Figures 1-4 relates to a valve operated in accordance with method Ilisted above, i. e. by the motion of one of the gun parts which movesdue to recoil forces imparted thereto. The particular mechanism shown inthese figures has special application to a Browning machine gun of thetype disclosed in the Browning Patents 1,293,021 and 1,628,226 and isparticularly designedA to be installed on those guns. It is understood,however, that this particular type of valve operating mechanism may beapplied to other guns having parts which move in recoil. The elementsdisclosed in Figures -14 are given the same reference numerals as thoseascribed to corresponding elements inthe Browning Patent 1,293,021 andreference is had to the disclosure in that patent; it is'understood thatthe operation of the Browning machine gun as disclosed in that patent iswell known since that particular gun has found universal use, especiallyin the United States. The parts added to the Browning Inachine gun inorder to carry out this aspect of my invention are given referencenumerals greater than 100.

A nozzle |0| with an integrally formed valve housing |02 is centrallyand stationarily mounted between the side plates a, a of the gun bymeans of screws ||0 (Fig. 3) and arms such that the nozzle is in thevertical plane with the gun bore and directed so as to guide a .iet ofcooling fluid into thecartridge receiving charnber barrel B. The arms|||v and screws ||0 are, of course. arranged so as to not interfere withthe normal operation of the gun.l p Y The valve housing |02 isformedffrom a solid .nozzle 0 I cylindrical block and has a hole |04(Fig. 1) therethrough in line with the hole in nozzle |0| and the highpressure supply conduit or passage |03, and also a hole |05 (Fig. 3)therethrough having its axis Substantially perpendicular to the axis ofhole |04. Axially movable rod or closure member |06 with reduced sectionor portion |09 passes through hole |05 and is adapted to normally allowthe iiow of cooling fluid from conduit |03 to nozzle |0| due to thebiasing action o1. spring |0'I which is mounted between housing |02vrand a flange |08 on the end of rod |06; when the rod |06 is moved to theright (Fig. 3) by means to be discussed later, the reduced portion |09of rod |05 is moved out of its normal aligned position'with hole |04 andiiuid is then prevented from passing from supply conduit |03 to the Rodor closure member |06 is moved to the right (Fig. 3) due to movement ofthe breech bolt E because of the interconnecting members: cam member||5, lever ||6, pivot rod |I-1l and lever ||8. Cam member ||5 projectingthrough slot |22 in one of the side plates a is adapted to contact thevupper right hand corner of the breech bolt E. (Fig. 3) and tobe moved tothe right as the bolt moves to the breech closing position; thismovement of cam member 'I |5 causes levers H6, ||8, which are rigidlyconnected to pivot rod ||'I, to rotate and to move the valve rod |06 tothe right (Fig. 3). Shoulder I |6s on arm I6 provides a stop formovement of cam |5 relative to plate a. Y

When the cam ||5 is in its furthermost right position with reference toFig. 3 the flow of fluid to the barrel chamber B is prevented. The timeduring which the iiuid valve is in open position as related to themovement of the breech bolt E is indicated by the limits |20, |2| (Fig.2); it

. is understood that fluid is allowed to be projected into the barrelchamber when the forward edge of the breech bolt E is on or between thelimits of |20, |2|. Spring |01is placed under compression so thatshoulder |68 on arm ||6 positively abuts against side plate a when thebolt E is on or between the limits |20, 2 Arms I6, I8 are madesuiiiciently long to bring about the above described operation and alsoso that the pivotl rod is carried forward sufficiently to clearoperating parts of the gun. A bearing block |30 for rod |'I is securedto the right side plate a of the gun by means similar to screws I3Collar |32 on rod ||1 abuts against the bearing block I 30 so as tosupport some of the weight of the mechanism. v

It is thus seen from Figs. 1 and 2 that cooling fiuid is injected intothe gun barrel B so long as the breech bolt E is in open position and isretracted sufficiently to allow the tip |25 of an ammunition round toclear the chamber of barrel B, i. e., the clearance between the roundtip |25 and chamber of barrel B is somewhat greater than the distancebetween limits |20, |2|.

A valve adapted to be incorporated in a high pressure gas systemdescribed as method 2 is shown in Figs. 5-9. The valve described inthese figures has an inherent time delay therein and seals well againstloss of gas from the barrel B. The valve proper does not project beyondthe normal cylindrical confines of thebarrel and the working partsthereof are confined by the wedge shaped member I0, which fits into acooperating groove in the barrel B. The'valve consists essentially of aspring |2, a cup-shaped member or valve I3 havingr three ports i3d`|317, |3c therein, and a ring or check I4 which is frictionally held bythe surrounding interior cylindrical wall I5, of the barrel B. Ring I4may partake of an oversized split resilient ring such as a conventionalautomobile piston ring. Ring I4 is moved bythe cooperating shouldersI3e, I3f on the cup-shaped member I3 as it, moves up and down in thebarrelfhollow portion or valve chamber I6 due to the gas pressure withinthe bore I'I of barrel B or due to the action of compression spring AI2,

Cooling fluid, for instance water, under high pressure of approximatelyVsixty pounds per square inch, is' introduced into the barrel bore I1through barrel channels or pair of passages and I9, channels I3a, i312,I3c and barrel channel 2i). Channels I3a, |317, I3c have the commoncentrally disposed channel I3d in communication therewith.

VIn the normal position, Fig. 6, the channels I8, i8 are closed byfrictionally held ring I4 so that` no cooling fluid flows into thebarrel. When a shell is fired a large pressure will be built up in thebarrel bore I1 causing the cup-shaped member I3 to move upward againstthe action of spring I2 and causing shoulder I3f to engage ring I4;further movement of member I3 will cause displacement ofring I4 andplace shoulder (3j in a position where it seals barrel ports I8, I9..Thus, no fluid will flow into the barrel as the cup-shaped member I3moves upward to its I highest position shown in Fig. 7 As cup-shapedmember I3 moves downward from its highest position due to loss ofpressure caused by the emergence of the fired projectile from the barreland due to the action of compression spring l2, ring I4, which isfrictionally held by barrel wall I5, will remain stationary and coolingliquid will flow from barrel channels I8, I9 to the barrel lriore I1(Fig. 8). Further downward movement of cup-shaped member I3 wil1 causeshoulder I3e to engage ring I4 and bring it into the port closingposition shown in Fig. 6. The elasticity of spring I2 and the amount offriction between ring I4 and barrel wall I5 will determine to a largeextent the time delay involved before cooling fluid may be injected intobarrel bore II.

It is preferred to inject the cooling iiuid into the barrel bore afterthe cartridge shell is eX- tracted from the barrel bore and before a newcartridge is inserted into the bore; in that case the time for fluidflow is approximately .02 second. The appropriate time delay and timeduring which cooling fluid ows may be subjected to wide variation by theparticular design of the spring |22, cup-,shaped member I3, andfrictionally held ring lll. l

A mechanism adapted to be incorporated in a low pressure gas operatedsystem, for instance, a mechanism operated by the muzzle gases of a gun,is shown in Figs. 10-l3.

In the above mentioned figures the flow of cooling fluid follows thefollowing path: from a source of pressure (not shown) of approximately75 pounds per square inch through inlet or passage a in valve housing 3,valve chamber 3| channels 32a., 32h, 32o in the movable portion 32 ofthe gas operated valve, port 33 in the valve housing 30, and thenthrough barrel opening 34 into the bore 35 of the barrel 3S.

Movable portion 32 of the valve is normally biased in its closedposition by means of compression spring 3'! and is moved to its openposition when muzzle gas pressure acts on piston 38.

Nut 39 serves to coni-lne the biasing spring 3l in the valve housing aswell as to jam the op- @site fend Of Sleeve. 4l? ascii-1st Packing 4l:S0 as. to prevent fluid leakage past the iiteriorcylind ricaly wall ofthe integrally formed shankv or valve closure: me'niber`32f which abutsagainst the free end of spring 31.

VNut 42 and packing 43 serve to prevent fluid lealgage'outfof the valvehousing 30 at the place Where piston rod 38 emerges fromnth'eV valvehousing.`

vThe piston chamber 44 for piston 38 is formed in a substantiallycylindrical block 50 which has a tapered portion 4.5screw`able'on theend of barrel 3Q, a hole 4t in alignment with the barrel bore, and atapped portion 41 in alignment with thepiston chamber 44 for thereception of plug at. The cylindrical biockso is screwame' on barrelt'to such anextent that a clearance 5I is provided between vthe. Vendofthe barrel and the cylindrical 'block 50,'. Muzz'le gases due to theburning of the ammunition in the' gunV flow through the clearance 5IVinto the piston chamber 44. A pin 52 which passes through cooperativegrooves in the barrel and cylindrical block' maintains those twoelements in xed position.

The piston 38 may be provided with a ring or packing 53 so as topreventloss of pressure past the outer wall of the. piston.

The integrally formed valve rnd spring housing 3Q maybe fastenedv to thebarrel 36 by'ineans oscrews 54, by welding or other similar means.

In al1 three arrangements disclosed herein a predetermined quantity ofvaporizable fluid is injected into the gun barrel, the exactV amountbeing determined by the applied fluid pressure,

. size of orifices leading into Vthe barrel 'and the timeinterval duringwhich the'particula'r valve is open. Since the last two mentionedfactors are fixed to a certain degree the most convenient manner inwhich the exact amount of fluid may lv be injected inthe gun barrelresides in controlling fiuid pressure by means well understood.

Iclaim:

1. A cooling arrangement for a gun having a barrel, means forming a'fluid passage in the barrel leading to the barrel bore, said barrelhaving a circular hollow portion therein in communication with the fluidpassage, a spring biased member in said hollow portion and responsive'to barrel gas pressure, a pair of spaced shoulders on the member, aring frictionally engaging the walls defining the hollow portion andadapted to close said passage, said ring being disposed between saidshoulders.

2. The'same as in claim 1 characterized in that the spring biased memberis within the normal confines of the barrel, and a wedge having a tongueand groove connection with the barrel -for maintaining said member inthel barrel.

3. A cooling arrangement for a gun, said cooling arrangement comprisinga barrel formed with a passage therethrough communicating with the boreof said barrel for admitting fluid under pressure to said bore, a valvedevice slidably mounted for longitudinal movement within a valve chamberintercepting said passage, said valve device in said chamber constructedand arranged to be moved away from said bore'by gas pressure within saidbore while maintaining said passage intercepted, and a spring withinsaid barrel for moving said valve device toward the bore and intopassage-opening position upon subsidence of the gas pressure within saidbore.

4. A cooling arrangement for a gun, said cooling arrangement comprisinga barrel formed with a passage therethrough communicating with the 7bore for admitting iiuid under pressurey to said bore, said barrelhaving a valve chamber intercepting said passage, a spring biased valvemember in said chamber havingla uid passage therethrough and operable bythe barrel gas pressure, and a second member surrounding theiirstmentioned member and frictionally held between the said first member andthe wall of said chamber and moved by said valve member toward the boreand into position opening said passage to iiow ofv fluid to the bore ofthe barrel upon the subsidence of the gas pressure in the bore.

5. In combination with the barrel of an automatic rapid re gun, ysaidbarrel having a bore, a chambery formed in the wall of said barrel,there being al first passage in said wall adapted to connect saidchamber with a source of pressure fluid, there also being a secondpassage in said barrel from said chamber to said bore, and valve meansin said chamber normally intercepting communication between saidpassages and responsive tcfchange in gas pressure in said boretransmitted throughr said second passage, to connect said first andsecond passages after a cartridge has been fired and before the nextcartridge has been inserted into said barrel;

6. Incombination with a gun barrel having an a ltion and then to cut 01Tsaid communication.

7. In a cooling devicek for a gun barrel, said barrel having a valvechamber and first and second passages leading, respectively, from4 avsource of pressure fluid to said chamber and from said chamber to theboreof said barrel, a valve movable in said chamber from a rst positionto a second position, said valve having a port adapted to place Asaidfirst and second passages in communication, said valve being adapted tobe moved to said second position by gas pressure in said bore, springmeans urging said valve to said first position, and check means moved byand in respense to movement of said valve to cut off communicationbetween said passages exceptv only while said valve, ismoving from saidsecond to said first position.

"8. In a cooling device for a gun barrel having a valve chamber andfirst and second passages leading respectively, from a source ofpressure fluid to said chamber, and from said chamber to the bore ofsaid barrel, a valve slidable in said chamber between Ifirst and secondpositions and having a port adapted to-place said passages incommunication, means urging said Valve into said rst position, saidvalve being moved to said second position by and in response to gaspressure in said bore, and a check slidably associated with said valveand coacting therewith and movable thereby, to cut oi` said firstpassage from said port when said valve is moving from said first to saidsecond position, and to open said first passage to said port when saidvalve is moving from said second to said rst position.

9. In a system for the fluid cooling of a gun barrel, a cylindricalvalve chamber associated with said barrel, there being a first passageadapted to connect said chamber with a source of pressure iiuid and asecond passage connecting said chamber With the bore of said barrel, apiston valve reciprocably fitting said chamber and having a portedcircumferential channel adapted to connect said passages, said valvebeing4 movable by gas pressure in said bore from a rst to a secondposition, spring means urging said piston into said first position, anda check ring fitting said channel and frictionally engaging the walls ofsaid chamber, said ring being reciprocable on and moved by, said pistonwith lost motion and cutting oir said first passage from said secondpassage when said Valve is moving to'said second position and clearingconnection between said passages when sai-d piston is moving toward saidfirst position under the action ofsaid spring means. I

l0. In a liquid cooling system for a gun barrel having a cylindricalvalve" chamber formed in its Wallja rst passage extending from the Wallo f said chamber substantially midway of its length and adapted tocommunicate with a source of cooling liquid under pressure, and a secondpassage extending from one end of said'chainber to the bore of saidbarrel, said system comprising, a piston valve reciprocably fitting saidchamber and having a circumferential channel in its periphery, portedfor communication with said second passage, said piston valve beingmovable by gas pressure in said bore from a first position in which saidchannel is in agreement with said `first'pas'sage'to a second positionin which said piston' valve partly cuts off said iirst passage, a ringtting and having lost motion within said channel and frictionallyengaging the wall of 'sai-d chamber, said ring and piston valve coacting`to cut off said first passage when said valve is in said secondposition, and spring means urging said valve to said rst positionwhereby' on decrease in gas pressure in said bore, said valve iirstopens said first passage to communication with said second passage andthereafter moves said ring to cut 01T said communication.

CHARLES E. BAILEISEN.

References cited yin the nie cf this patent UNITED sTATEs PATENTS NumberName Date 543,567 Browning July 30, 1895 783,050 Knapp et al. Feb.-21,1905 789,687 Edwards et al. May 9, 1905 797,237 Y smith Aug. 15, 1905799,884 Von Augezd Sept.` 19, 1905 940,101 Wetzel Nov. 16, 19091,064,197 Dawson et ai. June 1o, 1913 1,073,298 smith sept. '16, i913

